What is a good set of speakers or sound system for a somewhat low price?

I'm looking for a speaker system that i can play my music out of. I have no idea what the speaker market is like. I'm looking for something that sounds great and will definitely have amazing bass (I love trap music). Nothing huge but large enough to make it LOUD. I'm not great with audio systems, so it has to be somewhat simple(although my dad is actually a professional at this, he doesn't have the passion or money to get a new sound system). I would like to be able to connect my ipod, computer, and future iphone to it. I have a smaller bluetooth speaker with an output so i can connect my 3.5 mm audio jack to it or use a quarter inch adapter with it, giving the system bluetooth powers. I don't have a lot of money and it would probably be a birthday present or something, so I'm looking in the less than 300$ range. Any suggestions are greatly appreciated!
TL;DR
big bass
easy to use
300$

If you want good AND cheap, the only way to get it honestly is to look at reviews of systems, then try to buy a used system on Ebay/Craigslist etc for maybe 1/3 of the new price or less. Used stuff is not in great demand but electronic stuff
Think about it. As soon as you buy something new, it becomes used and loses a lot of its value. For $300 you might be able to get a $1000 system from someone who has a lot more money than you and now wants to buy a $3,000 system.
Aim for something local so you can go hear it before you bid, or at least before you pay, just to make sure it is in working order.

A good used stereo receiver (I like models from the 1970s)
and a pair of bookshelf speakers with 8" or larger woofers
should beat the living @#&!% out of what you have been using.

Connect the source to any line-level input
(Aux, CD, Tape, etc.) on the receiver.

Your father should be more than capable of

Well s'more, I have a set of Cyber Acoustic CA-3602 speakers that I use here for general use while at the computer to play music. They are a 2.1 system with about 30 watts rms and there's plenty of bass. The list price is $57.99 but can usually be had for less at places like Staples, Micro Center, Best Buy and others. I rarely turn them up past half way as I get complaints from the people two floors below my room. I have included a link and you can check Cyber Acoustics products out and they will plug into your computer and have an auxiliary input jack and a headphone jack and all plugs and jacks are 3.5mm.

http://www.cyberacoustics.com/store/Products/Speakers

Good Luck, keep your chin up and may the sun always shine upon your day.