http://www.pit-r.de/fidel/ <-- converter. Has some letters that are missing in the above.
A lot of people in Eritrea and in Ethiopia use this (not all languages though - some use english, and those who speak arabic probably use that script too).
This is a free dictionary someone amazing made for tigrinya: http://memhr.org
This is one for amharic if you're curious: http://www.amharicdictionary.com/
haha straight to the point. Memhr just means teacher anyway. He has some phrases and basic vocabulary and grammar lessons, so it's not just a dictionary smile I noticed that the amharic dictionary is more active has a voting feature, but people are adding words more than voting. Then again, the tigrinya one has one guy who updates it, and for free, so he must be busy.
There's this too: http://www.digob.com/Tigrinya-eritrea-ethiopia/Tigrinya-Dictionary-eritrea-ethiopia.php