I'd offer both sides at each feed and if Lo seems to want more you can start on side one again.
I've never timed a feed, I've always fed until they came off, then offered the other side.
There's no need to try to get a gap between feeds in the first few weeks, just try to keep your baby close and feed on demand. Feeds should start to space themselves out naturally.
The first few weeks are vital, but try not to worry about it, just feed your baby and try to accept any offers of help and be kind to yourself 
Don't think you need to express for a growth spurt, unless you really want to. Think its much easier to just feed, feed and feed some more when they hit. If looking after dc1 and feeding dc2 is a worry there are some tips here.
Is there a particular reason mw suggested fenugreek? Normally its not needed. Was low supply an issue last time? Have you spoken to a BFC about your concerns?
Which websites have you been researching on? I tend to go for the evidence based ones like kellymom, la Leche league, ask moxie and the booby whisperer.
Hope that answers all of your questions. Some other things that may help are putting the bfing helpline numbers in your phone, find out where your local bfing groups are and go along while you are still pg, google kellymom what to expect in the early weeks, kellymom preparing to Breastfeeding and dr jack newman videos. You might also like the books Babycalming by Caroline Deacon and the Womanly Art of Breastfeeding.
Good luck 