You can use rezStream Cloud in conjunction with Microsoft Word to create and print envelopes and address labels.
To do so you will first need to create a contact list and export it to a .csv file using this guide: http://support.rezstream.com/entries/97457918-Export-a-Contact-List-to-a-CSV-file
Then you can take that .csv file and import it into Word using the Mail Merge feature.
Here are some articles from Microsoft to help with that process: