I’ve been using these almost exclusively for my projects:
They are very sharp and really inexpensive. They work great as @WillAdams suggested above for my very small engraving, for larger engraving I have the 90 degree ones that Carbide3D sells as well as some small 1/8" 90 degree bits from same seller as above on EBay.
I used the ones above for these Christmas ornaments recently:
If you want any small text with detail you have to do V carves, I’ve done some larger stuff with small 1/16" (0.0625") flat end mills, but it was very basic text. Remember that if the angle is more acute it will have to go deeper for a given letter width, that’s why you wouldn’t want to use a 45 degree V bit to do 3" tall letters, …unless you use software that can limit the depth of cut (“Flat Depth” in some softwares).
Hope this helps 
Dan