Digital DIY is an active web page with tutorials, application articles and an active forum. Details of many TAP-28 applications are presented here and the forum is an excellent place to ask questions about TAP-28 use.
Many of the TAP-28 applications shown on these pages have been programmed using Swordfish Basic. The Swordfish Forum is very active with knowledgeable PIC users. A search of the forum can provide a lot of information when things don't work as you expect.
The Amicus Forum is the place to find information about Amicus applications and hardware.
The Proton Wiki page has all sorts of application information and links to the Proton Forum. Much of this information also applies to Amicus.
Sparkfun has many unique and interesting products to aid in development work with an ever-expanding product line. Check them out for components and breakout boards as well as tools.
The Sparkfun Forum is an active site covering both their products and development in general.
Sure Electronics is located in China and offers a wide variety of electronics items from components to systems. Generally, their products are of good quality and their designs unique and nicely done. Items may be ordered from their web page or from ebay.
Documentation for most items is available from the Sure Electronics Download Center.