Need help on 10Base2 Transcievers

[bendoor@hkucc.hku.hk]

Hi there
we recently bought a Mac for our lab with difficulty (usual departmental
financial problems....).  The Mac has an ethernet card with an AAUI socket and
our cables in the department are of thin ethernet (coaxial) variety.  I plan to
buy a 10Base-T transciever (is it the right transciever?) on my own.  I would
really appreciate it if anyone out there could help me. 
 Where can I buy a cheap one? Am willig to pay for shipping.
 Can I design one by myself?  (I'm just a poor student...)
 My e-mail address is
BENDOOR@hkucc.hku.hk
Regards
Jeethan
 
I'm new to connecting computers to networks and need help!