As long as the web part deploy successfully, first check that the feature is activated. If this is the case, and the web part is still not appearing then :
- From site actions –> site settings go to the web part gallery
- If the web part is not in the gallery, click on the Document tab then click the New Document button
- Find the web part in the popup list and click the checkbox next to it
- Click the populate gallery button
Tagged: Deployment, SharePoint 2010, Web Part, WSP
