Originally posted by tibbitts Is there a list of lenses + hoods somewhere?
For k-mount lenses, there is. Bojidar Dimitrov has a great website, with pictures and specs of most, if not all, Pentax-made k-mount lenses. His information includes the Pentax part numbers for the matching lens hoods.
Now, finding the right hood, especially for older models, can be difficult. For the kit lens from your K-x, that should not be a problem.
... or maybe it is. I just checked B & H's website. The carry the PH-RBA 52mm bayonet lens hood that is correct for your DA L 18-55mm AL lens. However they show it as "temporarily unavailable". WHen they have it, they sell it for $21.95.