Yes I agree, a digital dictionary is very useful for japanese language students, and for anyone visiting japan. If you don't know japanese at all, you can survive in japan with a Canon Wordtank.
I use the Canon Wordtank IDF-3000 , its kind of old but its still one of the best out there. I recommend this for beginners.
You can buy Canon Wordtank now at:
japan-direct.com/products.asp?type_id=14
But if a digital dictionary is out of your budget.
Get "Kodansha's Essential Kanji Dictionary: A Compact Character Dictionary for Students and Professionals"
It has the 1,945 common Kanji in a compact dictionary. Excellent for students.