Welcome to FT!
Welcome to United!
Just keep your eyes open and your ear to the ground for good deals.
The Mileage Run forum has a nice FAQ on MR's.
Download the UAL Easy Schedule electronic timetable. That usually will help you figure out how to plan out legal connections for MR's.
www.kayak.com is a good source to get an idea for fares. Usually most fares will allow up to three connections. For example a N/S fare from LAX to IAD on kayak might list for 300$, but tweaking some things you can make that into a 3 or 4 segment flight for little additional cost. Think, LAX-SFO-DEN-ORD-IAD.
Maybe something fun could be LAX-SFO-SEA-DEN-ORD-BOS-IAD.
Keep your eye on the MileagePlus promotions also. And, check your mailbox (email and physical) for targeted offers for EQM's.
Also, IndiaKane's fare search website tool is kinda handy to get some ideas as well.
http://www.indiakane.com/ff/ff.jsp
Since you're on the west coast, think International for almost instant 2P status. One R/T to BKK or SIN can get you up there. I belive that it's 16k miles R/T to BKK from LAX.
I recall one idioic MR I did just because UA was trying to build up business prior to Southwest invading PIT. I did TUS-LAX-SFO-DEN-ORD-PIT and back for $288 R/T, plus $59 for a night at the comfort inn. Of course, the die-hards would have flown back the same day....
I've always found that the UX flights were always a bit more pricey for MR's. I used to be based out of TUS, and all my business travel involved UX which made things quite pricey. That, and I HATE reject jets with a passion.
Good luck! I'm sure others in this forum can add (or subtract) to this advice.