Old Church Slavonic
by Todd B. Krause and Jonathan Slocum
This very useful material is provided on the website of the Linguistic Research Center (LRC), College of Liberal Arts at the University of Texas at Austin.
This valuable reference work is available at Slovari.ru
- in Russian contains over 10 000 words
Available in PDF
compiled by Carl Fredrik Gildea, University of Gothenburg
A short list of abbreviations is available at orthodoxepubsoc.org
A great transliteration tool
for a number of Slavic languages including Russian and Old Russian Orthography.