If you could state how much you're willing to spend on the various parts of kit we would be able to advise you better.
Manufacturer is generally more important then the style. Generally all airsoft aeg's work the same so how it looks like outside is up to you. Though the advice in the Airsoft Newbie Buying Guide about styles is good. Generally ak47, m16/m4 or mp5 are good starter gun styles due to the availability of accessories and upgrades.
I'll add my weight to the argument of cheap vs quality. Get the highest quality gun you can afford, you'll thank yourself in the long run. Upgrading a low grade gun to match a high grade gun almost always costs considerably more then simply buying the high grade gun in the first place. Not to mention having your gun break down on you in mid game due to cheap parts sucks rocks.
Another thing to consider is resale value. You don't want to spend too much cause you're not sure you'll stick with it? That's actually a good reason *to* get a high grade gun rather then not to. You spend $600 on a Classic Army gun and, provided you've taken decent care of it, you have a very good chance of recouping most if not all of that $600 back. On the other hand, the classifieds are continuously flooded with people trying to offload Aftermath guns with no luck.
Please keep in mind that the prices listed below are rough. I've seen each of the listed at the price given but that was months ago and I don't religiously follow pricing trends. They should be used as a guideline only.
For $200, the best you could manage is Aftermath (CYMA rebrand) stuff. Both the Broxa (full stock MP5) and the Kraken (AK47) are decent bargain basement guns, about $160 or so each. Stay away from Aftermath's Kirenex or Knight (both M4 variants) and the Lycaon (collapsible stock MP5) though, not a good rep.
If you're willing to go up to $300 you could get a JG. Yeah JG's are China clones but they're getting quite respectable nowadays. JG's M4 runs about $290. You could get one of the G&G M4's for about $340. G&G is the cheapest of the midgrade guns. $400-$450 would get you an ICS which is a slightly higher end midgrade gun. $500-$600 would get you a G&P, there's some debate on whether this is the lowest of the higrade guns or if it should rank higher. Either way they make nice guns.
If you can afford it, highgrade guns such as Tokyo Marui or Classic Army are the way to go. They're going to run you $600-$700. Though if the M4/M16 style is what you want then I'd recommend staying away from stock TM's, the barrel wobble and creaking are pretty bad on the stock TM M4/M16's (yes the new TM M4/M16's have fixed this problem, but the bulk of the ones in country are the old ones so best to just avoid them for now).
I did extensive research and settled on the Tactical Carbine version of the Classic Army M15A4 (basically a full stock m4) as my first gun. If an Armalite is what you're looking for then I think it's the best of all possible versions. You have the shortened M4 carbine barrel, which makes you less likely to smack your barrel off something when turning quickly, combined with the full stock which houses a large battery. Small batteries don't have near the run time of a large battery, not to mention that the reinforced slip ring (the ring that keeps the fore-grip on) is really stong. While this is mostly a good thing and a big step up over CA's previous M15 versions, it makes changing small batteries in the field very difficult if not impossible.
CA's M15A4 series in general is a big step up over their previous versions and as far as stock armalites go they're probably the best. All metal where the real steel version is, the plastic parts where the real steal version is plastic are made of high quality enhanced nylon fiber rather then abs for great texture and feel. Classic Army has a deal with Armalite so you get all the proper markings. Plus that deal also goes to show the quality of the manufacture, Armalite wouldn't put their name on a shoddy product.
Internally the gearbox is reinforced metal and all the gears are metal as well. It fires hotter stock then Tokyo Marui's as well, firing at 300-320 fps where your average TM only fires 280-300 fps.
All in all this is a great starter gun if you can afford it. Because it's all metal you don't have to worry nearly as much about breaking it and you won't get any of the wobble or creaking that is infamous in stock TM M4/M16's. Unfortunately affording it is the biggest problem, they're not cheap. For reference I got my CA M15A4 from the classifieds, upgraded with a bunch of Systema internals to fire 390fps, for $600 shipped which was a great price.
As you can probably tell, I'm a big fan of Classic Army. One thing to keep in mind about Classic Army is they now have two lines, a proline and a sportline. Originally they were easy to tell apart because the proline had the metal body and the sportline had a plastic body but recently CA has been releasing their sportlines with metal bodies. The price tag should still allow you to easily tell the difference, the sportline being $300-400ish and the proline never being cheaper then $500, usually more like $600 or more but it's still something to keep in mind. All the pros that I went over above were regarding the proline model. The sportline model has cheaper everything internally and externally.
There's alot of people that will expound the virtues of G&P as well. And I'll admit the externals of G&P are very nice, easily on par with CA, in some cases better. The reason why I don't say G&P over CA though is much the same reason why people weren't big fans of CA up until a few years ago: their quality control for the internals is not the greatest. That means a fair number of lemons. CA got a handle on this a few years ago and they've been making great strides in terms of their rep ever since, but G&P isn't quite there yet. This is simply my personal opinion and there are many people that would likely disagree with me, but it's something to keep in mind. ICS is about a cheap a gun as you can go and still get full metal out of the box. One thing to remember about ICS is they like to go their own way internally, so upgrading or repairing them inside will be more difficult then other brands. And needless to say it's not in the same league as CA or G&P. It's what someone on a budget but determined to get full metal would aim for. I should probably give TM some love here as well: Due to Japanese laws TM guns fire alittle cooler then most others and their externals are going to be almost entirely abs plastic. But *nothing* beats TM for internal reliability. You leave a TM stock internally and it will last for literally decades.
One of the perks of going with an M16/M4 variant is that mags are dead easy to come by and dirt cheap. You can get Star brand mags for like $5 a mag or less, plastic yeah but sturdy none the less (Star is also one of the few brands that makes realcaps too). Metal mags will run you a fair bit more, $15 to $30 a mag. There's no real reason to go with metal over plastic for mags except looks/realism. Though of course if you're going to go hicap then you might as well get metal ones. As to Brands, TM and CA make good mags. I've heard pretty good stuff about MAG brand mags as well. King Arms not so much, especially for M4/M16 mags. Star is always a good affordable fallback too.
Now for some gun pron:
My Classic Army M15A4 Tactical Carbine without external addons:
My baby, CA M15A4 Tactical Carbine with m203 grenade launcher, red dot sight and taclight: