Hey, nice! I just started brewing about a month ago and it's a lot of fun to do. I would put the barley away. It might not be crushed and if it is it might be too old.
Since you need ingredients. Check some recipes out there based on what you like to drink. Pick a recipe that sounds interesting and not too complicated, and bounce it off this forum to get feedback about what to expect.
An extract recipe is the simplest and least expensive. A partial mash recipe means you steep grains in a bag and you will use extract as well. All grain is the most complicated because then you have to deal with more equipment and more information/steps, but if you want to read up on it, then by all means give it a shot! Personally I'm glad my first try was extract.
You can scale down by converting pounds to ounces and then dividing from original batch gallons to your batch gallon size (5 gallons to 2.5 is an easy division, for example). I do this all the time with a spreadsheet. Most recipes are for 5 gallon batches, and my carboys are 3 gallons.
You'll need a kitchen scale to measure weights down to fractions of ounces as well as up to 11 pounds.
You'll need a stainless steel pot to cook in, probably the most expensive single part of the puzzle to start with... A 5 gallon pot will provide well for a 3 gallon batch size since you need headroom for foam and you will boil down a little. You'll need a funnel to get the wort into the carboy.
You also need an auto-siphon, some vinyl tube that will fit the siphon, clean bottles, caps, and a capper, but that you can buy weeks later.
Good luck! It's a lot of fun.
