I successfully ran some tests of mono in debian woody and freebsd 5.4. My best piece of advice is to read the documentation thoroughly:
http://www.go-mono.com/docs/
have a basic understanding of apache:
http://httpd.apache.org/docs/trunk/
and some basic asp experience:
http://www.w3schools.com/asp/asp_intro.asp
I dove into it with only beforehand knowledge of apache and wound up thrashing for a month until I combined these sites and some of the asp code samples already ready to be used in the mono package. Now if I could just code asp...