Paul,
There are a number of good free and pay Cisco emulators that are out there. They are an amazing resource for people who are trying to learn to work with Cisco equipment, but don't want to spend a ton of money setting up a full lab. Here's a few options for you:
GNS3 - GNS 3 is my personal favorite. It only emulates routers, so it won't help with switch labs. However, what it does is pretty impressive. It emulates the Cisco router hardware, so you can run standard Cisco IOS images on it. That means you get 100% of the functionality of a real Cisco router without the hardware expense. Its performance is not spectacular, which is what prevents people from using it in production and keeps Cisco happy, but it is great for a lab. You can learn more about it here: http://www.gns3.net/.
Boson Netsim - Boson Netsim has been around a long time. It is not an emulator, but a simulator. In other words, you are not running the Cisco IOS, but it is merely taking commands that you type and displaying results based on what would happen on real equipment. That means it does not give you 100% functionality like GNS3 does, but it does give you all of the commands that show up on the exam. It also supports switches which gives it a leg up on some of the other products. You can learn more about it here: http://www.boson.com/netsim-cisco-network-simulator
Cisco PacketTracer - The Cisco PacketTracer is another emulator like the Boson Netsim. However, it is much more polished and is a superior product in my opinion. It allows you to build a custom network and work to your heart's content. There are even entire online communities built around sharing PacketTracer lab files. The only issue with the Cisco PacketTracer is that you cannot buy it. It is provided free of charge to students enrolled in the Cisco Network Academy and not sold through any retail outlet that I am aware of. That being said, copies of the software can be found with just a few minutes of Google Kung-Fu. You can learn more about the PacketTracer here: https://www.netacad.com/web/about-us/cisco-packet-tracer
eBay - The final entry in my list is eBay. Sometimes emulation/simulation isn't good enough. Currently the exam features Cisco 2901 routers and Catalyst 3560 switches. If your pocket book is big enough you can pick up a handful of each and get to studying. If you are on a budget, though, there are alternatives. For example, my all-time favorite router is the Cisco 3640. It is a beast of a router that can support darn near every feature Cisco has to offer. You can find them all over eBay for under $100. They won't run the 15.x IOS track, but the 12.4 track contains all of the commands on the exam. Just make sure the router comes with the interfaces you need and enough memory to support the advanced feature sets. I recommend a 3640 with at least two Ethernet interfaces, 128MB of DRAM and 32MB of Flash. Keep in mind that you can buy one with less dram/flash and upgrade it pretty easily. On the switching side, the exam uses the Catalyst 3560, but a 3550 will support almost all of the features you need as long as you load an EMI image on it as opposed to the SMI image most of them come with. The hardware is the same, but the software image determines whether they support layer 3 routing or not. Like the 3640, these can be found all over eBay for under $100 each.
Hope that helps,
Don Pezet
Host, ITProTV