First, welcome to the forum!
Second, I just got my first crossbow this year. I started off on a smaller budget as well, trying to keep it under $300 (wife aggro and all!). The best for that price point is as rjd suggested, the Centerpoint Sniper. You can get it from Amazon for about $230 depending on the sale. Cabela's has an updated version with a few nice perks right at $300. There are tons of youtube videos on this bow.
I went to Cabela's and found it didn't feel good in my hands. It's heavy, right at 9lbs and the scope is obviously cheap. Even though I had read lots of great things about it, it just didn't feel good in my hands. I felt that if I couldn't get comfortable holding it in the store, I wasn't going to be comfortable in the woods where I'm potentially shooting at an animal.
So that left me a few options. I could either play my hand at getting a used xbow, or up the budget and justify it to the wife (took her to Cabela's and let her feel it... luckily she agreed). I decided not to go used for my first purchase as I wasn't sure what I should look for and didn't want to get something that wasn't right for me. I spent a good week reading reviews, watching videos, and reading numerous forums. I also visited several shops. Here in Charlotte, there are 3 near me. One didn't carry any but the higher end, the second was understaffed and after waiting 10 minutes and not getting any help I left, and the other when I told him my budget of $600 or less seemed to not want to help me anymore. Cabela's, the gentlemen helping me was nice but obviously did not want to be there.
I found from another forum an online store, Wyvern Creations. I called them up and spoke to the owner, David. He spent over 30 minutes talking to me and hearing me out about the bows I thought were right for me. He asked great questions like what I wanted to accomplish and what's most important to me (wants vs needs). He ended up agreeing that I made good choices and quoted me prices on both bows I had picked. They were the exact same price, so it came down to what I wanted out of a bow. He also didn't pressure me and asked me to sleep on it and call him when I was ready.
I would recommend giving him a call. He's a no pressure well educated guy who will hear you out.
Ultimately, I went with the Parker Hammer 325. It shouldered the best at Cabela's, shoots nicely, and has a good scope. Buying from Wyvern Creations, they also add a deluxe rope cocker and 4 extra bolts and field points. No sales tax and free shipping. I ended up right under budget of $600, but I feel confident about my purchase and look forward to getting out in the woods.
Hope this helps, good luck on finding a bow!