During the course of trying to tee off my main water supply pipe (to
feed a new sprinkler system), I've encountered the need to replace my
old 3/4" galvanized steel supply pipe with 1" copper pipe. I've
received quotes from three plumbers ranging from $700 to $1000, so I'm
trying to figure out whether it's the type of project that a plumbing
newbie can handle. I'm nervous about screwing it up and being without
water for several days.

I have a photo illustration of the project the project on my website
(http://snice.net/pipe/) that will give you an idea of the scale.
It's about 20" from the union with the city pipe to my copper
sprinkler tee. It runs uphill and jinks slightly, and having never
worked with copper before, I'm uncertain as to whether I'll be working
with a blowtorch to bend or joint my along.

Also with the connections, is it as easy as it looks? Just get a pipe
wrench and screw the pipes together?

Appreciate any insight.