README: add deps link and env vars hint

Change-Id: Id1962b1f2277625a40f854697e1572a78833efe6
diff --git a/README b/README
index c909f83..9dd736c 100644
--- a/README
+++ b/README
@@ -58,6 +58,26 @@
 configurations, see the command line options of ./gen_makefile.py.
 
 
+=== Build Environment
+
+For dependencies, see
+
+  https://osmocom.org/projects/cellular-infrastructure/wiki/Build_from_Source
+
+Furthermore, note that the makefiles by default install to /usr/local/*,
+so if your system doesn't have this by default, you should probably add
+
+  export LD_LIBRARY_PATH="/usr/local/lib"
+
+and
+
+  export PKG_CONFIG_PATH="/usr/local/lib/pkgconfig"
+
+to your environment. To use the installed binaries after installation, also
+
+  export PATH="$PATH:/usr/local/bin"
+
+
 === osmo-uninstall.sh
 
 Remove osmocom built binaries and headers from given prefix,