If you're doing PPC, find a couple of networks that have offers you want to promote (and think you can make money on) and then focus on those offers/networks. PPC is a numbers game, and the first step towards turning those numbers to your favor is getting on weekly payments. Most networks pay net-15 once per month, meaning your payments, for example, for all the commissions you generate in the month of June will be paid on July 15th.
However, Google charges you for those clicks loooong before that, and even if you're using a decent credit card, you're looking at having to pay for those clicks you generate at the beginning of the month long before you ever see any revenue from the affiliate network.
Without weekly payments, your growth is very seriously capped by your credit limit, and if you're just starting out in this economy, it's going to be pretty difficult to convince your credit card company to raise that limit. One way to turn the numbers back to your favor is to get on weekly payments so that you can pay down your credit card balance as you go.
Most networks want to see you generate $1k-$2k in commissions per week for about a month before they'll put you on weeklies. So, figure out if one of the networks you've already signed up for has some offers where you think you can reach those numbers and focus on that first.
Also, don't let the $1k-$2k per week number intimidate you. $1k per week on an offer that pays $32 CPA is about 31 conversions per week or a little under 4 and a half conversions per day. You can do that!