For the configuration section you will need 4 real switches. Routers could be emulated under GNS3/Dynamips. You can connect the gns3 world to the switches, using other switch has a breakout box, using qinq, you could emulate the physical connection of each router to the switch´s ports. This will looks like as you have each router connected to the switch, even cdp will work.
Other options are rack rental purchases.
For the troubleshooting section, there is no way to emulate the real exam under gns3. You will have to use the same configuration topology for training.
Cisco dont allow to share exam content or information, it would be better if you look around there for more information. But i have never seen rack rentals or nothing about the troubleshooting section, this could be the hardest part to get training on this.
There is a official training program from Cisco, Cisco 360. If you purchase this you will get access to real exam practices, both troubleshoot and configuration, training workshops, etc.