With webbrowsers there really is only AWeb, IBrowse and Voyager. Just try all of them, all three have good and bad points.
AWeb is nowadays free (as you've probably noticed ;-) and get little updates every now and then (
http://aweb.sunsite.dk/).
IBrowse is still waiting new version, but that might still be far away. Demo-version can be downloaded at
http://www.ibrowse-dev.net/ and registeration is available at
iospirit.de.
Like IBrowse, Voyager hasn't seen many updates in the viewpoint of normal 3.x user. Demo-version can be downloaded from
http://www.vapor.com/. There is also registration information, and Voyager can be acquired also with NetConnect3 -package.
Instant messenger - well, there is
Jabberwocky, which is nowadays free - I think other messengers for OS3.x are quite dead, but other are welcome to correct me on that. There is naturally some other active messengers available, but they are not for mainstream Yahoo/MSN -compatible.