I'm going to try and build a wizard to help people build these easier, but that will take a bit of time.

It's really quite easy. First you find a url that has querystring variables that can be easily changed.

Example:
http://jobsearch.monster.com/jobsearch.asp?cy=us&q=internet&zip=10012&rad=10&re=112&refine=1

Then you simply replace the parts you want to customize.

Example:
http://jobsearch.monster.com/jobsearch.asp?cy=us&q={Search Query}&zip={Zip Code}&rad={Radius in miles:5,10,15}&re=112&refine=1

Then you go to the page below to format the Url into a bookmarkable like.

Format a URL