[www.nwe.ufl.edu] this shows u all the tools and what they are used for, i take no credit for it i just simply found it on another forum and thought it would be helpful for u.
also to get new fonts go to [www.dafont.com] the way you insert new fonts into gimp is by first downloading the font, but open it instead of saving, then extract the file into My computer>>WINDOWS>>Fonts
Re-open GIMP and it should be in there
for new bushes u can either make your own or go to [www.deviantart.com] and searching GIMP brushes (also most .abr files tht are normally used for photoshop can be used with the latest version of gimp) download the brushes (download on the left hand side), now follow ure extractions program, i use winrar, simply opens up winrar with the files then u can extract then into the specific folder
EITHER:
My computer>>local disk>>Program files>>GIMP (version type)>>share>>gimp>>2.0 or later versions>>brushes
OR another way, my computer > local disk c > documents and settings > user > gimp > brushes
they will both show up in GIMP they are just simply put into another folder