Yes! On groups.yahoo.com, type what you’re looking for in the search box under "Find a Yahoo! Group", then click Search to scan the Yahoo! Groups directory for group names and descriptions that match up. You might be surprised how many groups out there share your enthusiasm for the topic!
Be as specific as you can with words and names—you’ll get the best results.
Note: Search results won’t indicate if a group is using the new Groups interface.