it is a shame that all you guys just see the physical side of these women!
you should like them for who they are, not what they look like!
ok, now that we have gotten past being pollitically correct, if you like a girl always ask her out for coffee or prehaps lunch or something simple like that. This gives you the oppertunity to chat and find out whether you guys can stand each other.

Find out if you have common interests.
Having common interests is a great excuse to see her again. Say she likes cycling, or bowling you can alway suggest that you guys should go togeather...
just be open, and honest.
also do not let failure intimidate you.

Most of the seccessful guys at dating have been knocked back more times than i have had hot dinners!

The more girls you ask out, the more girls that will accept.