As Char Jackson pointed out, it is the same as in XP; also, I replied to
what you wrote, not, apparently, what you meant, when you said "I had to
do a lot of extra typing until I found a utility that could set up the
environment variables, because W7 doesn't let you do it by hand".
But if you want an easy way, do what I do:
In a command window, run
echo %variablename% > env.txt
Now edit env.txt to your heart's delight, then copy the text (you know,
Ctrl-A, Ctrl-C) and go to the place I told you about. Highlight
(Ctrl-A) the environment string there and paste (Ctrl-V) the new one
over it.
Do be careful
I will more often create just the new environment variables in an editor
and paste them into an appropriate place within the existing string,
since that is safer (IMO).
E.g., I might paste a string like ";C:\Other Programs\" (no quotes) at a
good place in the existing path variable (the most common change I
make), or I might create a whole new environment variable and paste it &
its name into the New dialog.
I'll try to remember to see if I can make changes done in batch files
stick, but that will require a reboot, so I won't do it now.