First, welcome to the site...there is a lot of great information here...
Now, as for your detector...Firstly, I would skip Cabelas and go with a reputable metal detector dealer. 4-H (info@allaroundashevillenc.com ) is one of the guys on T-Net that has great customer satisfaction, there are others as well...You will get better prices and service here !!
We really need to know what type of MDing you plan on doing to give you a better idea of the unit we should prescribe....beaches(fresh or salt), parks/playgrounds, old fields. Are you looking for coins or old relics(civil war & the like)
That being said, if you are strictly on a price point...I would say the two most recommended units for beginners are the Garrett Ace 250 and the Tesoro Silver Umax. Both of these are great beginner machines and are of quality manufacturer. The Ace has target ID which gives you an idea of what you may be digging(coin/iron/etc), while the Tesoro Umax is a sound only machine. I personally prefer the Tesoros for several reasons. One is that you you will not be misled by the ID feature(sometimes a gold ring will ID as junk!!), Second, Tesoro has a full lifetime warranty and is super on warranty work, the Tesoro is super lightweight and, in this price range, is a really deep searching unit. Also, the Umax is a turn & go unit..not many things to learn.
Let us know some more specifics of what you wish to hunt for and maybe we can give you more info...Im sure you will get plenty of advice.
Brad