The short answer...
Beginner bow completely setup with 12 arrows & 6 broadheads $250 - $325
Climber tree Stand $150 - $325
Bag or Block target $25 - $50
Total Dollars $425 - $700.
Total Time - As much as you can afford
The long answer:
If you want new, a PSE Nova with sights & quiver is an OK new starter outfit for about $200, also Reflex has some for about the same $ that I like a little better. However, since you are just starting out the best advice i can give you is to go to an archery shop like Archery field and Sports or Central Iowa Achery and get set up. They will have a selection of starter stuff for under $300 including decent used equipment or lower end new stuff. They will fit the bow to you, accessorize it properly, fit the arrows to the bow and give you free range time and some shooting tips. Plus, when you need a tune up or new string or cables don't be shy about taking it back to them and they will be glad to fix you back up.
Tree stands ?? There are 3 basic kinds (ladder, stationary or climber). I'd recommend buying a climber for a first stand because you can use it almost anywhere and keep mobile. Cheap ones start around $100, the better Lone Wolf ones can be found for about $325. Depending on where you hunt, a ladder stand or stationary one may be better, but a climber is good most anywhere.
Time Commitment - Depends how adicted you get. Early season I go every dawn and dusk I can, when the rut is on I often spend the entire weekend in the woods, coming home to eat & sleep after dark.
I stil recommend going to Archery Field and Sports and ask for Irv, however like someone else said, if you know a veteran hunter they can help save you save some money if that is a big issue. They may have older equipment that fits you and you can borrow or buy. Or you can get a $200 bow starter set from Cabelas or somewhere, and your friend can help you set it up and make sure it fits and is accessorized properly. I will caution you on this though, If your friend doesn't actually know what he is doing he can cause you mega frustration with an improperly tuned setup.
IaCraig