personally I would steer clear of the walmart paint.
You would be much better off finding some citadel paint as it is a much better quality and is designed to be applied to plastic figures.
P3 paints are very good as well but I found they take a bit more getting used to.
Both are readily available either from a games workshop or any place that host warhammer type table games.
Also I would suggest starting small and getting 5 or 6 colors to start with and slowly build up from there, I know when I started I bought every color under the sun and half of them dried out before I even had a use for them.