Hi,
I am just starting to study for the CCNA and have absolutely no experience with a router. Barely even know what they are

People keep telling me i need to get experience with a router and my short labs at uni are probably not going to be enough. They say at the very least i should get a router sim but for the price of some of the good ones i could get a cheap second hand router off ebay.
I did a search on ebay for cisco routers and there are literally hundreds of them. With so many to choose from and all the numbers and features, i dont have a clue which one to get.
Heres my problem, i only have a pc with no nic except for an internal modem. If i was to buy a router, could i use it with a serial connection or through my rj-11 port on my modem or some other way? Also, having no other nodes on the network, is it worth having a pc with a router attached? Could i still learn how to set it up, configure it ect ect more so than with a simulator?
Any advice on what to get and why for the ccna would be greatly appreciated.
Thanks