How can I add words to and delete words from the dictionary?

[AC Question]

I am a Realtor and I want to add some job-related words that I use frequently to the dictionary so the G5 will not repeatedly offer corrections. I want to add my name (Lois) so when I speak it, the G5 will stop writing Louis. I also want to delete some words. For example, I often use the word inspection and when I swype it, I almost always get insurrection, and as a busy Realtor I just don't have time to participate in insurrections anymore. I know the phones "learn" eventually but until then, I'd like to give mine a little IQ boost.