I have NO ASP experience at all....
So with that in mind.. I say (from what I've seen elsewhere) go with PHP.
The analogy of learn to crawl before you walk doesn't really work here.. Its like Programming.. A lot of people start off with Visual Basic (Microsoft), and think that they will work there way up to Delphi (the superior product), but instead, they get stuck in B forever..
Anyway, as for hosts.. Almost EVERY Unix based server is now offering PHP/MySQL support at no additional cost. Also, there are Free Servers that offer it as well.. You wont find a Free ASP server since ASP can only be run on NT backed servers, and i haven't seen any free NT servers.
As for coding.. i don't know ASP at all, but i do know that PHP is pretty easy to understand. Its very similar to Perl.
Also, there are a lot more PHP resources out there... for scripts, communities, snippets, etc... Its a bit harder to find good ASP resource sites.
Anyway, I Recommend PHP...
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