Start by visiting Orco.com. Click 'Products', then click 'Retaining Walls' (up to the kinda-top-right in really small print), then seek the Do-It-Yourself info. You can download ALL kinds of DIY info. You're now at AllanBlock.com but that's OK. You now have 2 sites to peruse!
The keys to this job are a firm, level base; proper slope-angle on the landscape behind the wall, filter/landscape fabric (not weed block), drainage, and gravel backfilling. You may read about tying the wall into the slope. Depending on how much digging you want to do, you can get away w/it, maybe. (I'll leave it at that.) Tying into the landscape on the back side is to keep the wall from pushing forward. That is, if the wall is over a certain height. I'll let you read on that and make your own decision. (I can't see it from here ...)
My best to ya and hope this helps.
Jay J -Moderator
PS: Consider hiring a nephew or someone to help. I mean, 200' is a LOT of block to move!!! So goes the same for whatever dirt you're removing and moving ...