Aftermarket Car Alarm

Hello, I own a 2001 Honda Civic LX that I bought back in 2006 through an auction, and am tired of the aftermarket system it came with. I have taken the car to shops and they don't know what system is in it and the remote is not readily available. I'd like to get rid of it and get a new alarm system in there. This alarm will only allow me to open my car when I use the remote. If I do not have this remote, the car won't start without it and will lock up my steering wheel, so I can't use my keys to start the car.

I'm looking to get a popular car alarm system where I can easily find the remotes that work with it, and be able to get into my car without being forced to use a remote when I could use my keys. I've seen some systems online like on Amazon. Would it be cheaper to order a good system online, then have it installed, or just have the work done at a local shop?

Also, what is a good system for around $100 that will work in my Civic? Thanks.