Using a DC-DC step up converter with small solar panel
I have actually made something which required a chip similar to your needs. I ended up using the TPS61032 from TI for my project. You can find it HERE 

If you want the evaluation board then you can find that HERE.

I found this to be a very decent little chip. I managed to get 1A out of it at 5V pretty easily from inputs ranging from 3V down to 1.8V. Give it a try and I hope this was helpful to you.

ADDED:
Alternatively, you can go to places like digikey/farnell/mouser/RS etc and find their range of switching DC/DC converters and then narrow your search down by selecting the specs you want (min/max input voltage, output current, output voltage etc) and then finding a chip that way. You can then search google to see if that particular chip has an evaluation board somewhere too.