it looks like VBO in this example is a class he's created that constructs a GL VBO. his sucessive .Add calls are equivlent to your glvertex3f + gltexcoord2f calls, pos would be the sprite position on the map, w/h are the size of the quad that is rendered (note that he's actually creating two triangles here to make a quad.

but without knowing how his w+h are calculated and how the texEntry U1,V1,U2,V2 values are created, I can't give you any more information.

I've looked up on GTA files and rendering, I've found :

http://brain.wireos.com/?p=1673

A GTA 2 .Sty parser (and looking at that, are you parsing .sty files or have you converted them to textures you're using?)

and

http://gtamp.com/gta2/tools/

which contains a link to gta1-gta2-tool-source-code.7z released by jernej, inside that archive there's tons of code dealing with GTA1 and 2 data files.

I can't be certain without extensive study, but his STY editor does seem to suggest that there's additional offset information that comes with each sprite defintion.