Okay, now that I have found the password of my Account again, I'll give a answer to my own question.
I have found a Solution that fits my needs pretty well, as I am using a custom build script to compile my documents.
What Tobi meant was the search of TeX for the TEXINPUTS path. It does not seem possible to set this path from inside a LaTeX document:
(have a look at http://newsgroups.derkeiler.com/Archive/Comp/comp.text.tex/2006-12/msg01539.html)
My Solution is to export the following variables before calling pdflatex(Note: If you export a relative path, it has to be relative to the directory where pdflatex is called, the double slash means the folder should be searched recursively, which is what we need):
UNIX Systems:
export TEXINPUTS=./path/to/font/directory//:
export TEXFONTS=./path/to/font/directory//:
WINDOWS Systems:
set TEXFONTS=./path/to/font/directory//;
set TEXINPUTS=./path/to/font/directory//;
I have two compile scripts available in the directory of my document: compile.sh for unix systems and compile.bat for windows systems.
EDIT:
I forgot to mention that it is important to add
\pdfmapfile{=Fontname.map}
to the document, in order to use the font. (Replace Fontname by the name of the font). This spares the run of updmap, as we don't wont to involve system wide steps, just use our attached font.