It is indeed hard to find Vladigerov's sheet piano music. A lot of his music was published by the Sofia (Bulgaria)-based Muzika edition. It is indeed hard to find because I don't think they export their books. You can contact them at http://www.musicaph.com/instrumental.htm
Several (and extrenely rarely performed) piano cycles have been published by Elm Edition (you can find it online). The Universal edition has apparently published his pieces in the 30ies, but it has been out of print for many years.
If you have time and desire, you can also contact The Union of Bulgarian Composers http://www.ubc-bg.com/ They may also be able to help.
It is published by Masters Music http://www.masters-music.com and costs a mere $15.00!
Waterloo Music Company ended in 2004.
They make music
The JR Music Supply company is the type of company that provides musical products to its customers. The company is frequently used by a variety of musicians.
Many publishers have published and reprinted his music in the past. However, the copyright on the majority of his music (as well as most Soviet composers) was restored by international treaty in 1994 making the number of publishers who can publish Shostakovich works limited. Today much of his music is published by Hans Sikorski based in Germany. There is also the DSCH publishing company whose only purpose is to publish new editions of Shostakovich's complete works that correct all of the mistakes and editing that made their way into existing editions.
Maverick Country Magazine is published by Maverick Country Limited. It is an independent media company that focuses on country music content.
GraphicAudio is a company that publishes audiobooks. These audiobooks give the feel of watching an actual movie because they feature actors, cinematic music, sound effects, and narrators.
Q magazine is a popular music magazine which is published monthly in the United Kingdom. The magazine is today published by a German publishing company called 'Bauer Media', which is a company that is based in Hamburg but has its operations in fifteen other countries world wide.
It is published by Masters Music http://www.masters-music.com and costs a mere $15.00!
Wonderland Music Company was created in 1951.
Frisbie - music company - was created in 2004.
Waterloo Music Company was created in 1921.
Central Music Company was created in 1993.
Western Music Company ended in 1970.
Western Music Company was created in 1930.
Earwig Music Company was created in 1978.
Pentimento Music Company was created in 2007.