Some questions to ask yourself first:
1) Why? The Workshop (for all its faults) is much simpler to manage and is the recommended way of adding content to your server.
2) Do you have the bandwidth (both in terms of speed and monthly cap) to support the files you want to make available through FastDL? Chances are this will be a fraction of your monthly usage compared to your server (assuming you want to host your FastDL site on the same machine as your game and that your provider gives you that option), but it's a question you want to ask yourself before you get a nasty overage surprise at the end of the next billing cycle.
Did you Google "fastdl tutorial"? There are lots and lots of tutorials out there for fastdl. Here's a decent one to start:
http://svenskunganka.com/tutorials/other/setup-a-fastdl-for-garrys-mod.html. It assumes you have gma's you want to decompress and put on FastDL, which may not be the case (ie, you may already have the playermodel files individually available to you). Have you tried implementing FastDL and are running into a particular problem?
Personally I use FastDL only for very new content I'm adding to my server or testing out. Once I know I want to keep something, I'll create an addon on the workshop (or append to an existing one) and use the workshop method. Just my $0.02. Some people use FastDL exclusively -- it comes down to personal preference and available resources.
As for the PointShop aspect of it, you would add models to PS the same way, regardless of whether your content came from a Workshop addon or FastDL (in fact, it's a little easier doing it from FastDL files, since you know the path to the models without having to crack open the .gma).
