The safest way to certainly get my attention is to send me an e-mail with as much information as possible. Also it's a great idea to leave me a message in Skype, I'm online rather often so You might get an answer right away.
e-mail: mihkel [at] uba .ee
skype: mncpnc (or look for Mihkel Uba)
phone: (+372) 55 674asd asd 886 (languages: Estonian, English, German)
Don't be shy, leave a message!