I have never done 3a before and I would like to start learning. I would like a good website with good videos for trcks, exc. Also I would like some recommendations on 3a yoyos. I have a speeder and I’m getting a dark magic II… will they work?
A great site for learning 3A is this one:
http://www.begin2spin.com/index.php
It has all other styles as well, but 3A is in there and there is a nice amount of tricks that are listed for you to learn. 3A does not have the ridiculous amount of tricks that you can learn (like 1A) because it is a less common style and not many people make tutorials for 3A tricks that they make up.
So then, start here, and then when you have finished these tricks, make up your own!
The two yo-yos you have will work just fine (unless the weight difference is ridiculous, by this I mean more that about 5 grams). Whatever you have to start with is good enough. Later on when you have progressed more and have become used to 3A, you’ll begin to notice that two of the same yo-yo will play more natural (This is my guess, I’m not to this point yet). The reason you are told to buy two of the same yo-yo is because they will play the same (for the most part, ignoring machine tolerances) and will be predictable in rolls, etc.
In terms of what yo-yo to buy two of…it doesn’t really matter. Anything will work fine for 3A. Just don’t go off and buy a pair of raiders for some 3A madness. 
3A is hard, but it’s awesome you are starting it! Don’t give up and keep practicing; 3A is, if anything at all, very impressive.
if i had a dollar for every time i heard this question id have over 9000.
simply as the others stated it dosent really matter what you are using as far as yoyos, two differnt yoyos will make rolls more difficult and unblanced. but just pick up a set of yoyos you already like, and start 3a from there. its not as difficult as it seems people kind of make a big deal about how difficult it is. and as far as tricks go, google search 3a tricks and what not. watch 3a freestyles to see what kind of tricks they are doing. if you also learn the terms of 3a stuff becomes much more understandable. 
3a all day took the worlds out of my mouth. 
you want to cut your string about 3 to 4 inches shorter than 1a lenght. later on in ur 3a expirience
you should get a pair of protostars or northstars. or just look on bst for some 3a yoyos.