I've been doing some searching for pre-built 27-inch wheels myself, and found the pickings really slim. There are some very reasonably-priced "Dimension" wheelsets available from JensonUSA and Bikeparts.com, but they're built with an Alex X404 rim that seems to be over 26mm wide. That's wider than I want, and probably wider than you want or need for 32mm tires. (You really don't need anything very wide at all. 32mm tires work fine on rims of 15mm, and 26mm is really wider than recommended for them - see the chart about 4/5 of the way down this page.)

I've carefully avoided learning how to build wheels over the years, but this may be what pushes me over that edge.