It's definitely worthwhile to circle back and revisit websites you've viewed before. Perhaps there've been new developments or maybe you overlooked something valuable on an earlier visit. That's also like true for Steve Morse's treasure chest of one-step tools, found at:
http://www.stevemorse.org/.
You'll find seventeen broad categories of research gold:
- Ellis Island (1892-1924)
- Castle Garden (1855-1891)
- Other Ports of Immigration
- U.S. Census (1790-1940)
- Phonetic matching and Soundex
- Canadian and British Census
- New York Census
- Births, Deaths and other Vital Records
- Calendar, Sunrise/Sunset, Maps
- Dealing with Characters in Foreign Alphabets
- Holocaust and Eastern Europe
- Genetic Genealogy (DNA)
- Creating your own Search Applications and Viewers
- Publications
- Awards
- Biographies and Interviews
- Miscellaneous
Each folder has lots of interesting stuff, not just genealogy-related items. For example, under the "Miscellaneous" category, you can find out about silent bidding (sniping) on ebay or view Obamacare healthplans or see Morse's lecture schedule and abstracts of his talks.
All our family's Irish ancestors were in the U.S. by 1850 so Morse's immigration records haven't helped with research on those family lines (yet). However, today I played around with Ellis Island and Castle Garden queries. Depending on when your ancestors immigrated, querying only on the town (townland) name and Irish ethnicity might lead to valuable chain-migration leads.
You'll quickly see the pitfalls here which are present with all databases -- empty data fields, mis-spellings, and bad transcription. Even misunderstandings about the questions asked, i.e., did the traveler consider "residence" as where he originated in Ireland or where he was going in America? Errors were possible at every point in the process; illiteracy, bad spelling and poor hand-writing are a lethal mix. I noted an entry where "Cappawhite" became "Cakkawhite." One has to be very careful not to narrow the search too much.
I'd love to share your successes and/or unique approaches with Steve Morse's site. Please email me at
blog@IrishGenealogical.or 
