I have gone Bert's route as well. Also looked a lot at other people's assembly to get some ideas.
Here are some tutorials, that I thought were pretty good, and some more assembly info:
http://www.picbasic.co.uk/forum/showthread.php?t=222
Darrel often says the best way to learn is by looking at the *.lib files, like pbppic18.lib. The assembly is pretty well documented there. More info in his post here: http://www.picbasic.co.uk/forum/showthread.php?t=6363&p=38604#post38604
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