i am not a admin so don't take my answers official but i am a forum hog so i know all the answers!!
#1 What kind of time should we arrive at? 
Well on friday i am not totally sure, me and joosebug are planning to get there around 2pm-3pm. maybe earlier to help set up/
#2 can we still get seats next to eachother?
If you check the seating plan i am sure there is space for both of you to sit next to eachother, if not i am sure if you request on the forums, and the other person agrees then they will swap for you.
#3 is the venue easy to find
Its not that easy to find for the first time, the instructions are clear though, What i mean by not easy is that it is not on a main road, more in a residential area.
#4 are there any shops etc closeby for us to go buy mass energy drinks from? 

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There is a small shopping place nearby with a villiage cafe, takeways and a Co-OP store. There is a ASDA near by that is about a 15 min drive.
Hope i answered your questions, i am sure CD will be on any minute!!