For Rx Pt D, go to medicare.gov and click on that first green button....Find a Plan. Input the Rx used , pharmacies used or mail order, and then find the plans. When you find some plans that look interesting, click on the plan name to see further details about plan premiums and Rx costs.
For Medigap supplement plans, try here
https://medicare.oneexchange.com/
If you go to the red "Getting Started" tab, you won't need to register .
You'll find different alphabet plans from cheapest to most expensive/comprehensive.
To determine what the alphabet plans cover:
https://www.medicare.gov/supplement-...e-medigap.html
One consideration in the beginning: it is not easy to change supplement plans later w/o going thru underwriting
(medical screening) so in the beginning you might want to pick a more comprehensive plan since it seems to be
easier to downgrade than to upgrade later.