Here are places you really must go, cuz they have stuff you really must have. Mkay?
P.O.N.D.
Petz Offset Number Directory. No longer updated but I'm leaving the link
here as it might be useful in at least reducing the changes of a clashing
offset. It's too bad there isn't a current list like this.
Carolyn's Creations
Carolyn is an amazing hexer. She's discovered so many things and done so
much. And her tutorials are wonderful. She doesn't just tell you how to do
one little thing she lets you understand how it works so you can do almost
anything. I couldn't be hexing today if it wasn't for Carolyn. Besides her
tutorials she also has lots of cool hexed breeds (duh), and lots of other
invaluable tools hosted on her site, including Nicholas Sherlock's amazing
programs.
AmberZoo
AmberZoo is a great site with resources and general information on Petz,
Oddballz, and Babiez. As well as other virtual life games like Creatures.
This is where I found a fix to allow Oddballz to work in Windows XP.
Birdy's Petfile Info
Viewer
This thing is really cool. It lets you see all the history in your pet's
file. You can see exactly how many generations your pet is, and what kind
of linage it has.
Sherlock Software
Nicholas Sherlock's wonderful tools for petz. Nick has made so many wonderful
things, prefect hexing tools, and a great addition for petz with lots of
incredibly useful features. You really need them!

BoingDragon is cool. This is where I got my counter from.
Resource
Hacker
Resource Hacker is an okay "hexing" tool. It has it's quirks though, and
you can't edit everything in the file. LNZ Pro can do everything that
ResHacker can and more, without the issues. So I don't know why anyone
would still use it, but I'm leaving this link here for now.
Hex Workshop
There isn't much I still have to do in an actual hex editor, but for those
few things I use Hex Workshop.
Crimson Editor
Crimson Editor is a text editor that lets you highlight and edit text in
vertical columns. An amazing time saver for hexing! Like changing the color
or anchoring a large amount of spots at once.
TextPad
The same as Crimson Editor, you can highlight and edit vertically. I
personally haven't tried this one, but it should work just as well.
HTML-kit
I use HTML-kit for all my html editing. It's a lot easier than just using
notepad for newbies like me, and it's got lots of tools that should be
useful no matter what your skill level. And it's a lot better than those
awful what-you-see-is-what-you-get editors like FrontPage. *retch*

Firefox rocks. Seriously. It's much safer, easier to control, more secure,
and has better features than IE. Plus, their logo is a cute little fox!
What more could you want? Get Firefox now!
All Forms
The cgi form host I use. It's free, ad free, easy to use, and has good
features.

I use BFN for all other cgi scripts. I picked it at random cuz I liked the
name, but it's pretty good. It's got lots of scripts, is ad free, and easy
to use. There are limits on the number of free scripts you can have, but
the limits are pretty high.