Oakball - A's Fan Central  a great site for A's fans...includes an active message forum 

Jen's Oakland A's Page  lots of player photos and a guestbook with some funny comments from A's fans

Tim Hudson Fan Page

Other Links

Major Leaguer - Index of Player Pages  a catalog of over 200 fan sites

Carlos Guillen - The Mariners' Great Shortstop  the one and only site dedicated solely to the M's Venezuelan shortstop

Arod Central  an interactive Alex Rodriguez fan community