how much should i aim for payout per lead

If you don't have organic traffic, then you're going to need to (1) do PPC or other paid methods, and (2) figure out how to remove the "fear" of losing money...try doing a small budget on a daily basis of only a few dollars.

Regarding your original question on what offers to promote, EMAIL and ZIP submits are easier to get paid on, but the catch is you have to find CHEAP traffic, and doing that via PPC can be difficult. If an offer pays out $1.20 and has a 20% conversion rate, and your CPC is $0.20, will you be successful? In this can yes (5 visitors = $1.00 cost, and 20% conversion = 1 commission of $1.20. So a $0.20 profit, or 20% ROI), but it's NEVER as easy as this basic forumla.

What's the quick way to figure out what you can afford to spend? Check your CPA network or Account Manager and find out what the "network EPC" rate is. This tells you what the MAX you should be spending since it's an accumulation of all marketing efforts for that campaign.

So if you're going to do PPC -> CPA for email or zip submits, use networks that have cheaper traffic such as Yahoo Search Network, MSN AdCenter, tier-2 PPC networks, facebook ads, or even Google Content Network if you do it correctly).

My advice is to just do the campaign...you might loose a little, but you'll gain MUCH MORE by actually doing it and learning from the expereience.

Good luck!

- Jeff