I was in your shoes the first of January and now I have about 150 items listed, 63 positive feedback rating on ebay, and things are starting to flow. My advice is just jump in and start selling, but do your homework on your items.
To download pictures from dropshipper
Right click on picture
Save target as My documents/pictures
To add pictures to your site
Click upload button
go to file-my documents/pictures
double click picture you want
click upload
I think I covered it all.