Magic tricks are for the audience's amusement, hence in order to get the best results you've got to get funny and enjoy as well. As they say, Enjoy the process. Don't pressurize yourself for the perfect output.
You do not need to be funny to "get the best results". Magic doesn't have to be silly or even comedic. My performances are not funny - they do have humor in them, but overall they are fairly somber affairs.
Personally, if all I do is make my audience laugh then I have probably failed at my goals. I look to create powerful emotional experiences for the audience and really make them think about things.
Making a world class performance can be done for free. The list of books RealityOne provided is excellent but really, if you pick one trick and just work at it and develop a meaningful presentation for it. Or even one prop. I remembering reading about this guy who was doing a walk around gig. A patron came up to him between performances and asked to show him the trick he (The patron) knew - and then proceeded to blow this magician's mind with the best thimble work he had ever seen. The patron had played with this thimble stuff for 40 years. It was the one thing he did - he knew no other magic at all.
Personally I have focused on a few select effects (Note- effect, not method or trick) and have really worked on how to make those powerful. I would like to think I have succeeded.
I think that being poor can be a major advantage in magic - because it forces you to make the most out of every purchase. It's much harder to simply fall into the habit of collecting methods if you can't afford the newest shiniest products. But like Daniel Garcia, who's family could only afford 1 volume of Tarbell a year, when you're poor you have to study that material thoroughly.