I'm wondering where I can find things that make regular Sims look more robotic, cyborg, or android like. Steampunk as well.

Sofar these are the ones I've found but I'm hoping there is other stuff too:
Robot arm: http://www.modthesims.info/download.php?t=450143
Half-robot face: http://www.thesimsresource.com/them...oid/id/1232985/
Shiny Skins: http://www.modthesims.info/download.php?t=440794
Contacts: http://www.modthesims.info/download.php?t=358932
Eyes: http://www.thesimsresource.com/down...yes/id/1072627/
Eyes: http://www.modthesims.info/download.php?t=450143
Glowy eyes: http://www.modthesims.info/download.php?t=395663
Visor: http://www.modthesims.info/download.php?t=483424

I also want robotic things that hang off of the face, like the Borg from Star Trek, but haven't been able to find any.

Here's what my google "search" found: steampunk

http://www.modthesims.info/d/275722
Are you still looking?

TSR steampunk section:
http://www.thesimsresource.com/them...skipsetitems/1/
Robot skin:
http://www.digitalperversion.net/ga...4&topic=19995.0
No eyebrows:
http://modthesims.info/download.php?t=456634
Ears:
http://www.thesimsresource.com/memb...ars/id/1072630/
This?
http://modthesims.info/d/416190
Doll skin:
http://blog.sina.com.cn/s/blog_71be8a2d010110q7.html
http://plumb-barb.tumblr.com/post/7...in-has-a-lot-of
Outfits unlocked:
http://fuzzylogicdishwasher.blogspo...g-unlocked.html
Servo:
http://www.modthesims.info/download.php?t=391993
Core head
http://www.modthesims.info/download.php?t=519775

The stuff Enriquebell put is pretty helpful! I too was making an android sim and this was all good!