Where are the cheap solar panels?
 

Looking for 2 5w battery tenders, a 10 and 2 15+w units for the summer toys, tractors and the diesel pickup, but they are rather pricey. For a large solar panel the price is down to $3 a Watt, why no cheap battery tenders?

Larger panels are more popular thus made in larger batches which drives cost down. Smaller panels while using less material stil require similar time to assemble and made in smaller quantities drives cost up. Its just like anything else really.

You could look into cheap individual cells on ebay, and build them into panels yourself. (Plenty of videos on youtube on the subject.)

make your own, what you want to do is buy CLASS B solar panlels,

they produce as much power aS CLASS A but at way less as they have VERY MINOR imperfections on them so have been rejected from the factory, you can pick them up really cheaply from ebay,

plenty of youtube videos on it aye,

Like mentioned before ebay is a good source. I got 2 of the 45 watt solar systems from Solar - Harbor Freight Tools

When it was on sale for $140. Comes with panels, charge controller mounting bracket and cfl lights. May not be the best source if your not in the U.S.

Here is a way to increase solar power output by 20-30%.
A Simple DIY Solar Tracker - Hack a Day

All of the $1 a watt heavy kaneka gsa60's sold in 2009 sometime.