Packet sniffers

["Marios Papaioannou" <m.papaioannou () cytanet com cy>]

Dear all,

I am interested to use a  packet snifer and I would like to know if there a
 site that compares various packet sniffers  to chose the most  suitable
for me.
Apart from that,  I would like to know if there are available  Ebooks  on
the web about packet sniffing tools especially Ethereal

Thanks in advance,

m.P