Bankroll: 3,000$
Poker History: Been playing poker 12 years on and off

I usually play 1/2 or 2/5 NL, but I just experienced a huge swing which crippled my bankroll. I live in the U.S. so my only option is live poker at Foxwoods.

Can I apply an ABC playstyle to limit and be profitable?

Raise AQs+ in position, set-mine, flush-mine (AXs)...

Any comments on some differences in playstyle would help.

Also, with 3,000$, what limit should I play?

You're asking a book's worth of questions and the standard on here is to read Ed Miller's Small Stakes HE. You should also read the faq's stickies.

I'd play w/e they have closest to 10-20, some will say start lower w/ $3K.

Turns out I have no clue about limit hold em'. I read a few of the stickies and a bunch of posts here.

People talking about playing A9o and raising K9o in position. That is nothing like No limit. A9 will lose you huge pots in NL.

What are they trying to accomplish playing A9 and K9 and K10...even if you hit top pair, I would still feel uncomfortable.

Various plays are made for different reasons based on the player's style and analysis of the situation. The ones you mention would be, most likely and generally, isolation raises and blind steals which can be fine but less effective in lower limits, imo. In limit a bad play can be bad but it's not going to stack you. If you keep up w/ the same mistakes over and over, and the same situations do come up over and over more rapidly in limit, you will lose a lot but if you learn from the mistake you'll be good going forward.

Like I said, you're asking a book's worth. Read SSHE and maybe some other well known player's book also. Play tightish (and lower) to start would be my advice until you feel comfortable.

Probably your only question that can be answered in less than a couple of hours.

300 BBs is sometimes considered a minimum BR for a good player, so 5/10 if it's available. The problem is that you're likely not going to be a good LHE player when you start and that'll relegate you to the 2/4 or 3/6 rake trap games.

Nonetheless, I'd still recommend the smaller games while you retool your poker thinking- ala LHE concepts that you should be learning from books like Howard recommended and reading the strat posts here.

Welcome to the LHE side of the world. In LHE you can't nit it up and then hope to double up with a big hand. The nuts matter less in limit. From the perspective of games you're used to, there are no huge pots.

I assume that if people are correctly playing A9 and KT they're thinking they stand to have the best hand and aren't worried about losing stacks.
In really soft games maybe. Your proposed simple starting hands are too tight and if that's what you consider ABC to be, then no.
Moving to a new game and from what you've said, you're not a winning player. Losing players don't have a BR. I'm confused why 15 buyins at 1/2 for a winning 2/5 player wouldn't be plenty. As a winning NL player, why would learning and then grinding limit be attractive?