Switching to e4?

For long I've played d4 and the London at every chance with white, but I'm starting to think that I might do better in the sharper positions that arise out of e4. How can I start to make this transition? Are there any openings in particular that I should look into?

If you want to play a really sharp opening, you could give the Danish Gambit a try, I highly recommend it!

Will do! Care to play a few games or so with it? haha 

My First Chess Opening Repertoire for White
https://www.newinchess.com/media/wysiwyg/product_pdf/9033.pdf
https://chessbookreviews.wordpress.com/tag/vincent-moret/
Opening Repertoire 1 e4
https://www.newinchess.com/media/wysiwyg/product_pdf/7819.pdf

1 e4 A Comprehensive White Repertoire

https://www.chess.com/blog/logozar/1-e4-a-comprehensive-white-repertoire-blog-preview
Openings for Amateurs by Pete Tamburro
http://kenilworthian.blogspot.com/2014/05/review-of-pete-tamburros-openings-for.html
https://chessbookreviews.wordpress.com/tag/openings-for-amateurs/
https://www.mongoosepress.com/catalog/excerpts/openings_amateurs.pdf

A Simple Chess Opening Repertoire for White

http://www.jeremysilman.com/shop/pc/A-Simple-Chess-Opening-Repertoire-for-White-76p3916.htm

http://www.gambitbooks.com/pdfs/A_Simple_Chess_Opening_Repertoire_for_White.pdf

Playing 1.e4

https://www.qualitychess.co.uk/ebooks/Playing1e4CaroKannandothers-excerpt.pdf

https://www.qualitychess.co.uk/ebooks/Playing1e4FrenchDefenceSicilianSidelines-excerpt.pdf

https://www.qualitychess.co.uk/ebooks/Playing1e4SicilianMainLines-excerpt.pdf

Keep it Simple: 1.e4

https://www.newinchess.com/media/wysiwyg/product_pdf/9068.pdf

https://www.chess.com/blog/HanSchut/review-keep-it-simple-1-e4-by-im-christof-sielecki

Might be a good idea to first read Discovering Chess Openings.

https://web.archive.org/web/20140627114655/http://www.chesscafe.com/text/hansen91.pdf

Well, you may wish to weight your studying time to 1e4 defences based on how likely you are to face them in general. So a look at opening explorer reveals that 1...c5 is twice as likely as 1...e5.

You may wish to have a few simple easily learnt, but none pressing lines for less common faced defences. As you continue to migrate you can then devote time to the minority defences after achieving some competence in the lines you choose against the big four: Sicilian, Symmetrical e pawn, French, and Caro Kann.

OP you may want to look into the Simple Opening Repertoire linked by @kindaspongey above. It concentrates on getting into an IQP position where feasible. You can use this as a starting point, then learn open Sicilian theory and possibly replace the Italian Game with the Ruy Lopez or Scotch later.