I would highly recommend Vallejo paints.  They are acrylic, have a great consistency and stick well to plastic.  If you can find a full color rack, there are a bunch of them.  I have to go to a general hobby shop that stocks wargaming pieces and models to find the full line, but Hobby Lobby also carries a few of the colors.

 "I was thinking of craft paint but that seems a little thick in the pigment department and I hear it doesn't stick well to plastic. Any thoughts?"

   I suggest a little experimentation with whatever you can buy locally. My local shop has a good selection of Tamiya so I use it but I also use lots of artist's acrylics, some oils, and tons of craft paint. I stopped airbrushing solvent paint many years ago and get along fine without it. It's very handy to just dump the airbrush in a big bucket of water to spray it clean. If your acrylics aren't sticking well to plastic try spraying a light coat of Testor's dull coat from their small spray can first, it seems to create a nice surface for additional paint and dries very fast....DaveB  

I found a large rack of Vallejo paints at a store that specializes in radio control hobbies.

I have been using their paints and I like them.

I airbrushed some acrylic craft paints recently, cheap Delta Ceramcoat and Apple Barrel paints bought at Michael's.  I mixed them with some Future Floor polish, which is just a clear acrylic, and some windshield washer fluid.  Mixed well, the blue tint doesn't show up. 

I used a bread tie chucked in my cordless drill to mix them well, then I poured them in the airbrush bottle.  it seemed to work, though yellow I needed to put on about 8 coats. 

Give it a try--they're cheap, and the odor is next to non-existent.  I can't see why you couldn't use them for brush painting or airbrushing.

While there are some that swear by cheap and easily obtained "craft" paints, I've never had what I consider acceptable results with them. I use Vallejo almost exclusively now, and I was NOT a fan of water based acrylics. I always felt solvent base paints were superior for airbrushing and their ability to stick to almost any material. Enter Vallejo.  Far and away the best paints I've ever used, acryl or solvent. The pigments are micro fine, the carrier sticks well to almost anything, and they lay down with brushes almost as good as if airbrushed. They can be difficult to find, I just order them thru my LHS, which appends to be a Hobbytown USA. I generally get them in 3-5 days and don't have to pay shipping. I can't recommend Vallejo enough. They will change your mind about acrylics.  They are the best paints I've ever used, especially for brushing. Try them!

I have airbrushed craft acrylics but was not happy with the results. I did not add future floor polish. I tried future as a clear coat once and tossed the rest of the bottle. I hated it.

I am going to source some Vallejo paint. Being acrylic I wonder if it will be a hassle to bring it north of the border. I am certainly in a mail order situation. Nearest hobby shop is 2 hours away and they don't carry much. They don't even answer my emails. I have a Michaels 45 mins away. I will check into them.

I do use craft paint in my structure modeling. I find them good for dry brushing wood etc... 

Micro-Mark's new Micro-Lux paints are made by Vallejo and they're named to match PolyScale colors where possible.

We did a First Look on the Micro-Lux paint line in the March 2014 MRH:

/magazine/mrh-2014-03-mar/fl_microlux-paint

I decided just for the heck of it to google Vallejo paints and the first choice that cam up was Amazon.  Checked them out and they carry an extensive selection of the paints individually and in sets.  I can't comment on the pricing as I am not yet in the market so can't say if they have a fair price.

Thanks, Joe for reminding me of that article. I will wait until Nov 1 when there is a model train show I can attend, only a 2 hour drive! and if they don't have any Vallejo there I will put an order in with Micro Mark! Thanks for the tips fellas!

I should also share that I have found a new acrylic paint supplier in Canada. George's Trains of Toronto is producing airbrush ready paint for the Canadian market.

https://georgestrains.com/proto-paint/