Below are links to products that I have either owned, or have used extensively and would recommend them to you. All links are to Amazon.
Inline Fabrications Light for Dillon 550
A nice addition to add light to the Dillon 550
Hornady One Shot Case Lube
If used properly, you shouldn't have any stuck cases when resizing.
RCBS Chargemaster Lite
A great digital powder dispenser that comes with check weight to calibrate.
Hornady Die Lock Rings
These are my preferred lock rings because the lock screw does not go into the die.
Frankford Arsenal Media Separator
This is used to separate the tumbling media (wet or dry) from your cleaned cases.
Lyman Flash Hole Uniformer
This tool uses common threads and can also be used in case prep centers.
Lyman Pistol Case Guage
This is a handy case gauge that checks multiple common handgun calibers.
RCBS Rock Chucker Supreme
This unit is built like a tank and is arguably the best single stage reloading press.
Frankford Arsenal Case Trim and Prep System
This is the machine that I used the most for my case trimming, chamfer, debur and primer pocket work.
Lee Powder Funnel
I've used other more expensive funnels and I keep coming back to this one. It fits .22 caliber cases better than some of the other brands.