I want to eat cheaply in Spain...how much will it cost PER DAY on average?

I expect to see a simple answer like:
Breakfast: $5.00 US
Lunch: $7.50 US
Dinner: $10.00 US
Snacks: $3.00 US
Drinks: $5.00 US (For One)

Bonus Question: How much do I have to pay for the next hotel category up above hostel?

Breakfast, WAY less, like about 2 鈧? but then you might want a snack, as the Spaniard do for midmorning. That might run bout $5

Lunch: about 10鈧?if you want to go with a Men煤 del D铆a, but you can get away with a tapa or two (betw 1.5 and 3鈧?each), or just buy a bocadilla for around 2 - 7 鈧? You can vary it, or go to grocery stores and pick up a picnic style mix, or just eat rolls, as I did when I was young and living on the cheap.

Dinner can be about the same as lunch.

Snacks, totally depends on what kind of snacks you want. A cup of coffee is about 1.25 - 1.50 鈧? Treats can run pretty high if you want, or you can go fairly cheap, depending, as I said, on what you want, and where you buy. You want to sit at a caf茅, you pay much more than running into a little shop and buying a bag of chips, or a pastry, and eating it sitting on a bench in a plaza.

Drinks run about 2 鈧?each, unless you're sitting on the Ramblas in Barcelona, then you can expect at least 5鈧?(they're bigger, but not enough to warrant the hike. That's for the location).

Take any figure and multiply by 1.5 to get the US price.

AND 隆BUEN PROVECHO!

Where exactly are you going? That DOES affect things. For instance, in Granada, we found, you CAN NOT buy tapas until after 8:00 PM, whereas in Sevilla, you can get tapas at 10:00 AM until about 10:00 PM. customs vary.

Lodging varies greatly. There are hostels that run up to four stars, and there are Pensiones at 1 star. There are hostels at four stars that will cost less than a 2 star, and your best bet on that is to look it up yourself. Find places in the locations you want to stay at. If you are travelling alone, and don't care about being at specific places, want to take your chances, it's, like a third to just walk in of what you pay making reservations over the intrnet. I would DEFINITELY go winging it if I didn't have a family to worry about.

I can only answer that question if I know where you are going because everything varies in price in each region.
If you want to eat cheaply your best bet is to avoid restaurants and eat as much fresh food as you can from a supermarket. Fruit will be great value. For a main meal have the menu del dia (menu of the day), that will be around 鈧? ($10). Stick to bottle water, agua con gas (fizzy water), can't get cheaper than that, but if you want a cheap wine you'll get that at the supermarket in cartons. It can cost as little as 鈧?.40c ($0.60c) a litre.
Hostel prices vary from region to region. Difficult to answer that one.

For food, it all depends of the location... if you are in touristic areas, you can forget to buy a menu for 10 EUR, if you are in a big city like Barcelona or Madrid, you find everywhere cheap food.. find a small restaurant, away from the big comercial avenue, buy a "bocadillo" of tortilla for 3 EUR and drinks.. buy them in the supermarket.. much more cheaper.. They have a lot of fast food as well.. and this is very cheap or cheap italian restaurant: Gino Restaurant, VIP Restaurant (Hamburger), where you are sure to eat well and have a good service.. but if you are in the islands or in a touristic area.. look carefully as the prices can vary a lot. Good luck.. and try to speak spanish so they won't try to put the price higher!