Watch the Level 4: Jazz Blues Soloing online guitar lesson by David Hamburger from Take 5: Jazz Blues Soloing

Here's how to not be freaked out by altered chords: just think of them as "extra-dominant" dominant 7th chords. It's like this: It's the b7 in a dominant 7th chord that gives it its tension, that makes it want to resolve, like when a D7 wants to resolve to G minor, or a G7 wants to resolve to C minor. Making a 7th chord an altered chord just ups the ante, that b13 or #9 adds another level of tension to the situation, some additional "seventh-y-ness" that's asking to be resolved.