Is there a good web site somewhere that describes the distinctives of each type of action? I know they overlap some in application, but are there some generalizations?

Yes, right here. Look at the Glossary page for your answers.

Surf rod and steelhead rods come in all types of actions. Live bait are usually extra fast.

Made that too easy!

They aren't so much different actions so much as completely different types of rods. Steelhead rods are normally fairly long, 8-9 foot, and somewhat slower action, live bait rods are fast tipped with a soft tip as you can cast a small live bait without killing it. Surf rods are long, anywhere from 8-15 feet, and fairly stout so you can cast heavier weights or lures a good distance from the beach. Each type of rod will have several different models or actions, so the possibilities are endless.

Martin , that is one of the perks of building your own rod . You can take an existing blank and extend it , or in some cases cut a little off to get thet "perfect" feel , or action you are looking for. Like Phil said , the possibilities are endless . Good luck . John

Let me add that I am thinking about this for an 8.5 foot light surf/pier/jetty rod. I fish conventional and have already built two surf sticks (one Lami, one Allstar). I would like to be able to get down to 1/2 oz and up to 2 or 2.5 (occassionally lob 3). Does that prompt other thoughts?

Rainshadow 1025F hot shot blank will work 1/2 to 3 oz.

Loomis also offers one, 1021-2. 3/8 to 4 oz.