The Daily Digi has an extensive list of links to tutorials.
http://thedailydigi.com/new/
If you look on the right hand side of the screen you will see a list. I clicked on the drop shadow one (since you mentioned that) and there is a link in there for almost every program a scrapper uses. There is a link for a PSP tutorial on drop shadows.
I didn't look through all of them -- but I imagine that most of them have links for PSP tutorials. Don't worry about the version of PSP you are using. The commands might be slightly different -- but you will be able to figure it out. PSP's basic stuff hasn't changed significantly since PSP9 (which I hated at first).
HTH