I've been building wheels since the 70s. Learned when I worked in a shop and there was no such thing as pre-built or factor-made wheels. If a customer bent a rim, we simply cut out the spokes and relaced it with a new rim. A lacing pattern is easy to learn from a book. Tensioning and dishing properly is something that's learned from experience. I'd definitely suggest a
tensionometer if you decide to build your own with little experience. And you'd need a truing stand and dish tool. Not sure how cost effective it would be for a single set of wheels (cheap truing stands are fine if you have a dish tool also). I think it's doable for a beginner if you're willing to spend time studying the method. If you're close to Wayland, MA I'd be willing to help you out.

This wheelbuilding book is available for downloading for a small cost and is quite good.