Well looks like you got the hang of fritzing! it a good tool, Now im just making sure that you do relize that where you have the D2 pin on the output of the arduino, you will need to hook each Dpin up to a relay IN so you have 4 relays you will need 4 more relays 8 in total if your going to use all 8 solenoids and all 8 Digital outputs D2~D9, right now you only have 1 active solenoid (D2 to IN1).
You may already know all this and just did a basic example on fritzing, but as you said you are new to this so you may not know? Ive been at it for about 6 months so im no guru but you will learn quickly. does that make sense to you so far you would use another wire to do from arduino D3 to IN2 on your relay board, and so on until you get to IN4 on your relay board, at witch point you will need more relays.
One other thing that makes me wonder is how much current the solenoids use, and if your powering them from a different power source, because you may be pushing the limits of a USB or even a 9 volt for that mater, depending on the power requirements of the solenoids.
Also if your just using one solenoid for now to try and get things running, looking at the code it says 2008, sometimes sketches work differently with different versions of the arduino IDE, if your using the newest version, V1.01 or even V1.0 I find V023 is a good stable version, and use it quite a bit, actually. you may even go back a little bit further and try V019 or so. If your using windows 7 some where around version 018~016 it stops working, I had some code I wanted to use, and it was based on V014 and would not load, so I downloaded every version up to about 017 I think b4 it would actually load up on windows 7 and the code was not compatible. I mention this because ive had programs compile with no errors, and not work in real life, then I would try it on a different version and it would work.
So their is some more ideas for you,and im sure others will chime in eventually with more help, I would look to see what version of the IDE the code is working on for others sometimes the mention it in their posts.
Hope this may have helped. If not maybe you learned something?
Good luck