well ive been doing alot of research on the subject as well so i have a small list of information about it....first off check out http://www.carsound.com the forum on there has some good advise on it...
I love fiberglass and a member of a really good forum on it. Here is the link...http://groups.yahoo.com/group/glassmanscustomforum/
Also like Goddy posted select products is a great company with excellent step by step videos. On that forum once you are a member you can view previous projects. Hope this helps