Here's some tips:
How to Fill Awkward Silences - wikiHow How do you handle awkward silences? - Yahoo! Answers
You can also create the awkward turtle:
Urban Dictionary: awkward turtle
Of course, this is just for basic interpersonal interactions. I have no idea if it works for romantic interactions. You may want to check out the seduction community for that:
Seduction community - Wikipedia, the free encyclopedia