Totally feeling you on the nesting kick already! I have already gone through my girl's clothes NB-12m and given away the ones I wasn't planning on keeping forever (cause we're having a boy and this is likely our last). I've been making lists of stuff we need to get before baby arrives and going through stuff/cleaning like crazy!
As for birth prep, I'm having a home birth so mine will be a little different. I plan to have the following ready:
rebozo, exercise ball, heating pack
food and drinks for people
stuff to make cupcakes for birthday and other activities for the big sis (who will be 3)
just making sure I'm stocked up on all normal essentials
For the week after:
lots of ready to heat and serve meals
stuff for a sitz bath, herbal supplements, squeeze bottle (as mentioned above), pads
breastfeeding "kit" - basically everything I may need when I'm relaxing wherever nursing for a long time and no one else may be around. like and basket of chapstick, nipple cream, granola bar, book, water bottle, etc.
I'm trying to remember everything from last time but my brain is fuzzy. I just remember I needed a warm compress on my right side each time I had to start the nursing session on that side because my let down was slow on that side only. and I spent a lot of time on the couch nursing so it was nice to have a bunch of stuff to do /eat/drink/that may be needed within reach (before I was good at babywearing). And we had a basket of diapers, wipes, and everything by the bed (we co-slept from day 1) and in the living room so we weren't running around getting something each time. I'll post more if I start remembering things from last time that were helpful or that I wish I had!