Okay, I think you should start at the top. First step, download the correct drivers from Steinberg for your computer, super easy, here is the link.....
Start : CI Series | http://www.steinberg.net/ There is a button for downloads, click and follow the instructions. Next, any headphones will do, Fry's Electronics has these in stock, typically for 13 bucks, Amazon sells them for the same, free shipping. They work just fine and come with a 1/4 inch adaptor.....
Amazon.com: JVC HAX580 DJ Style Monitor Headphones: Electronics
Although the Vypyr has USB outs, I think for lots of applications like playing along with Youtube jam tracks, the headphone jack routed into the Steinberg is the better route for realtime (zero latency) use. I would get a stereo male to two mono female plugs adaptor, so as not to short one side of the headphone amp. Also, many DAWs, including the one I am about to recommend, only support one audio device at a time. Your SM58 is a very good microphone, lots of well-known singers even use it on their records, like Bono of U2 and Mick Jagger, so you are good to go there. Now, go download Reaper, and worry not about the length of your trial, many people I know have used it far longer than 60 days, be sure to download the 32 bit version, as most freeware VST available is 32 bit, and your laptop will happily hum along. Once you have the drivers downloaded, go to your computer control panel, and make the Steinberg your default audio device, and plug your speakers into it instead of into the computer directly. It will pop up as one of the options when you click on the audio section of Devices. Once you have Reaper installed, go to the top row and click on Options, and go to the very bottom of that list, and select Preferences. A box will open, go to Audio/Devices. Select ASIO as the audio type, the Steinberg will appear as the input, you must click "Enable Inputs" to get it to talk to Reaper. Set the buffer to 256, and if there is a software page for the Steinberg, set it for 256 also. Click okay, and you are good to go. If you can figure out Audacity, Reaper will seem pretty easy. Now, go to youtube and search Quist Jam. He is a friend, he has lots of tracks to play along with, and with the Steinberg as your default audio device, plug the guitar amp headphone output into the Steinberg, and play with the mix control so that you can hear the video and the amp together. Voila, jam city, over the speakers or headphones. If you don't have iTunes, get it. Make it your default audio player when you import things. Youtube also has lots and lots of drum tracks played by guys with nothing better to do. If you search "Youtube to MP3", you will find a little converter that will turn those drum tracks into an MP3, and you can then import them into Reaper on a track, and build a little song around it. You are just fooling around, nobody cares, they are just happy to help someone get started. With these tools, all FREE, you can do amazing things without too much hassle or learning curve. And Reaper has a terrific forum and lots of helpful people if you get stuck. You may also PM me here, and I will send you a bunch of free VST things I have found online, keys, effects, dynamics. Have fun!!!!!!