Tell you what, I've got my old DX5e that I haven't used in quite a while. If you're in the US so shipping isn't nasty, I'll sell it to you for 30 bucks plus shipping. Should be able to put it priority mail. I've never had an issue with it but I obviously won't guarantee anything. I upgraded to a dx8 is the only reason it sits. Occasionally I use it as a trainer to teach new pilots but I still have a DX4 for that.
Otherwise, the DX4 is a pretty decent radio and like Bolvon72 said it's great with the super cheap receivers from hobbyking that are under 7 bucks.
If you are looking for something better, the Turnigy 9x has a huge following on here. It has a lot of cool features and if you search the forums I'm sure you'll find more than a little information on it.
I probably should have asked what it is that you are trying to fly first. What are your goals for flying? That will determine your transmitter.
This would most likely do what you need. But If you intend to get a radio that you can grow with you might want to keep looking around. Something like a DX6i is programmable and allows you to program several models but would be well above your 75$ price point.
But if you are committed to the hobby and pretty sure you will be flying for a while and buying more planes...
If you think you'll be flying other models and growing into more complex models you will not regret having more channels and options like expo when you get better models especially more acrobatic (less stable) models.
I'm doing the same thing, starting with the Nutball. I was actually waiting for the parts for my Tricopter to arrive from China and got hooked on the build videos. I had ordered the Turnigy 9x and got impatient, so I ordered the HK 6 channel from the US warehouse. The 9x beat it by one day.
For the price, the 9x is nice. But if you just need something to get started, the HK @$29 and here in three days, can't be beat.