I found the treadmill cheap on Craigslist. It's not important what kind of treadmill you choose but it makes your life easier if the hand rails are simply bolted on.
I found the desk locally. I got lucky and found an adjustable desk for only $50 locally.
Step 2: Treadmill Modifications
I wanted the treadmill to not stick out, but I also did not want to put too many hours into the process.
1. Remove all unnecessary parts. I removed the hand rails, the incline motor and the hinged incline wheels. I added some black painted 2x4's to make the treadmill level (you would not have to do this but my incline motor would not stay level).
2. Modify the control panel - there was a lot of unnecessary plastic on the control panel so I took that apart and using a hack saw cut the board to a smaller size. I did have to move some of the boards around to accommodate. I don't like the look and eventually will make a new control panel, but this works fine for now. I simply used a zip tie to keep the emergency key engaged - hope I don't fall while walking!
That is all I did to the treadmill other than giving it a good cleaning and adjusting the belt tensioner.
Step 3: Desk Modifications
The desk I got adjusted from 34" to 44". To be comfortable typing on the treadmill I needed a few more inches.
1. Removed the top of the desk
2. Placed a 4x4 in between desk base and top. Screwed the base into the 4x4's and used a few L-brackets to fasten the tabletop to the 4x4's
3. Painted the 4x4's black so they blend in to the frame - does not look bad at all.
Step 4: Test And Install
I set up the desk in my garage to give it a bit of a test run - worked great!
I went to work early one day and took apart my old desk and moved it all to this desk. A few things help:
1. I had a 25' long vga cord with a 3.5mm audio jack, so my computer tower is tucked away Ina corner - leaving a cleaner look and more room on the desk.
2. A wireless mouse and keyboard are great for the same reason.
3. I simply slide the monitor over when I am on the treadmill - takes me about 15 seconds to raise the desk to the correct height.
4. I have a stool that I can sit on that works at my standing height - it takes awhile to be able to stand all day.
5. Invest in some good insoles and a nice pair of shoes for the treadmill. I use a pair of Cushies when I am on my treadmill - they are comfortable and also look nice enough that if I forget to change back to my dress shoes for a meeting I am not wearing sneakers.
6. Be prepared to be a bit of a show for awhile if you are the first in your workplace to move o a standing or treadmill desk - they will stop by.
7. Persistence - your feet will be sore and you will need to figure out the best speed to walk and for how long - but it will get better and you will be more productive and have more energy throughout the day.
Step 5: Cost
1. Treadmill - $80 on Craigslist
2. Desk - $50
3. Other materials - $0 (random things from garage)