A few things to note:

• A quality down sleeping bag will last a decade or more, and perform just as well or better than a synthetic bag, but will run you $200+. A synthetic bag will be marginally cheaper, but only last you about 3-4 years depending on amount of use and maintenance. One option I found was the Kelty Cosmic Down 20 (I see at least one other person recommend it here). It's a cheaper beginner down bag, good for three seasons, stuffs down small and is light, but not ultra light. Sierra Trading Post had them on sale a little while back, so check them out. I got the long version for $150 after tax, shipping, etc. Plus, they have a lot of 30% discounts for $100 or more, and even if you get the coupon after your purchase you may be able to get it applied retroactively (I did).
• Military Surplus. It's dirt cheap and extremely rugged, but heavy as hell. Personally, I use a Gen2 UMSC ILBE main pack, with some modifications to reduce weight. It's still 7 lbs on its own, but cost me $90. If you buy an Osprey, you're going to get a fantastic lightweight pack, but it will be closer to $300 for one that is as large as my ILBE. If you're a big person, like me (6'4", 230 lbs), the ILBE may be alright for you. It holds 5200 cubic inches of volume, and will stand up to the worst punishment you can throw at it. They are built to be "Marine Proof," meaning easy to use and hard to destroy.
• Pack size is key. If you buy a large pack, you'll be tempted to bring everything you can with you. That's a mistake. Think minimalist. How long will you be out for? If it's a weekend trip, a 50L pack is all you need. Only bring essentials, and no backups unless they have multiple purposes. If you go out for a week or more, you'll need a larger pack, but mostly to hold your extra food.
• Hammocks!!! Ditch the tent, if you're going anywhere there's a lot of tree coverage. There's nothing like sleeping on air, and hammocks are super easy to set up, tear down, and get used to sleeping in. You'll want to consider a sleeping pad and base layers, though, as the wind will be sapping any insulation you may have gotten from the cold ground. Take it from me: a good sleeping bag is not enough for a hammock. You'll want to consider that you'll be more exposed too. Hammock camping is basically tarp camping, but off the ground. Your "shelter" is just a tarp strung between two trees. This provides a more natural camping experience, but also exposes you to the elements. Learn how to secure a tarp in high wind/rain scenarios. Price point is another benefit. Eagle's Nest Outfitters sells a double nest hammock for about $70, the rain fly is another $70, and the straps are about $30. That's $170 for a shelter system that will give you more comfort (you're off the ground), and reduce your weight by POUNDS. It's a good investment. Tent campers are losers, in my opinion (no offense). Get off the ground, where the critters, rain, and rocks will impede your good night's sleep.
• Dual purpose gear! It's a state of mind: don't bring anything that isn't good for more than its intended purpose. For example, one of my favorite pieces of gear is my rain poncho: used as a poncho, it keeps me dry; rigged as a pack cover, it keeps my belongings dry; used as a ground cloth, it will provide a surface to keep your stuff off the ground while you set up camp; used as an emergency shelter (think tarp), it gives you an option to survive the rain overnight if your rain fly fails for some reason. My bear can, as well, is both a protector from critters and a camp seat.

There's so much to learn when you start backpacking. Just do your research and you'll find so many smart ways to save money and protect yourself on the trail. Good luck, and see you down the trail!