I've tried G Adwords but even if I have some conversions I have no profit (I spend more than I earn).
Share your experience here.

the key to ppc in my opinion is you need to test and tweak

Once you have tested and find a product that converts you need to take a look at your keywords that are converting for you.

Then optimise your pages to get a higher ctr which therefore gives you a lower cpc.
What i mean by this is get rid of the keywords that are getting you clicks but not converting.

I would take a look at keyword elite you can find some great 0.5c keywords that can help your roi....

yes ppc is alot about testing. sometimes you have to lose money the first few times to find a winning keyword or winning campaign. Also yahoo is very good or Facebook advertising. I would also use ppv traffic very good source.

hope this helps to the top

I believed it really depends on the campaign niche. Some niches are profitable on a specific network.

Google adwords works for me all the time. However, I have a gadget campaign that is doing well in Adcenter compared to adwords campaign.

7search has great tools for ppc, but I personally like yahoo and msn right now...I try avoiding g adwords right now, there is plenty of other traffic out there for us to not solely rely on g adwords. Also facebook ppc is pretty hot right now especially since FB just topped google with traffic rankings

7search works very well for me.