Devdutt

http://devdutt.com/articles/indian-mythology/krishnas-best-friend.html

His Guru

His First Guru is Brihaspathi

Uddhav Understands Krishna Balarama Through His Guru Narada

1. http://www.srigaurangashram.in/significance_of_rath_yatra.html
2. http://www.salagram.net/parishad129.htm

More

1. http://www.purebhakti.com/teachers/bhakti-discourses-mainmenu-61/22-discourses-2003/354-sri-narada-munis-ecstacy.html
2. http://www.purebhakti.com/teachers/bhakti-discourses-mainmenu-61/22-discourses-2003/355-sri-uddhavas-guru-rsi-narada.html

Audio
http://www.radhanathswamimedia.com/brihad-bhagavatamrita/more-brihad-bhagavatamrita-narada-muni-meets-the-yadus-uddhava-and-the-queens-of-dwarka/

Kyari / Video

http://www.brajfoundation.org/uddhava_kyari_nandgaon.html
http://www.brajdarshan.in/uddhava-kyari/

https://www.youtube.com/results?search_query=Uddhava+Kyari 

Stream

Udhava is told to

1. follow a stream of water and when he would reach the source of the stream he will reach Yashoda Nand Maharaj’s home. 
2. The stream is made from Nanda Maharaja and mother Yashoda’s tears !!

http://www.forthepleasureoflordkrishna.com/tag/udhav/

Speaking tree

http://www.speakingtree.in/search/all/Uddhava

Swami Narayan

http://www.swaminarayanmandirdowney.org/bajaria_31.html
https://www.youtube.com/results?search_query=SHRI+RAMANAND+SWAMI+THE+GURU+OF+LORD+SWAMINARAYAN

Akbar

http://surdasa.blogspot.com/2012/01/akbar.html