The Hardware Shopping MegaThread
^ that thread shows some other locations you might be able to shop from. i think ncixus
will work for you w/o the additional taxes.
if a p4 is doing ok for you then getting an i5/ i7 htpc might be overkill.
why would you not like an amd cpu? for the price you pay, their cpus have great bang for buck. you can get an amd quad-core for $100 that should easily be able to handle what you want.
if you really would like to stick with intel, then an i3 dual-core should work too.