LADY GAGA
http://www.ladygaga.com/theremix/
To promote the album 'The Fame', Lady Gaga did several performances worldwide. She also performed on various american television shows and performed in Vietnam for a beauty pageant during the swimsuit competition. Three songs off The Fame were used in the series Gossip Girl and she performed the single 'Pokerface' on American Idol. She also performed on Xfactor and then talked about her upcoming tour. Performing on programmes like these targets the right audiences as people watching are people interested in music and are mostly young people that would go to a concert. Also, news that Gaga would be appearing on the show would have spread so the audience watching are most likely fans. To celebrate the launch of the show Dirty Sexy Money, ABC created a music video of Lady Gaga's song 'Beautiful, Dirty, Rich'.

The album received further promotion from her first headlining concert tour The Fame Ball Tour. For her album 'The Fame Monster' which was combined with The Fame as a deluxe edition, Gaga did a Monster Ball tour over all the main cities in the world. This is targeting an international market. Merchandise such as t-shirts and glasses were sold at these events to promote her album. Alternate versions of the show with minimal variations were planned by Gaga to accommodate different venues to suit the different target audiences. Her concerts and merchandise are mostly aimed at teenage girls to young woman and her many gay fans. The genre of music is pop.

An active twitter and face book account can help promote an artist and is a great modern way to keep fans updated and to advertise upcoming albums, videos, gigs and more.
GREENDAY
http://www.greenday.com/billabong_splash/index.html
Green Day is an American punk rock band formed in 1987. Green Day was originally part of the punk scene.
The band's early releases for independent record label Lookout! Records earned it a fan base.
As the band have been going since the late 80's I think its hard to say a specific target audience although the majority seems to be teenagers or young adults involved in the punk scene. To promote their albums Greenday go on worldwide tours to promote to as wider audience as possible. This is called global distribution.
Greenday also have a twitter account and a face book which lets them communicate with their fan base and let them know new updates involving the band.
JUSTIN BEIBER
http://www.justinbieberofficial.co.uk/home
The album My World is R&B influenced pop and is compared to the work of artists such as Michael Jackson, Stevie Wonder, Chris Brown.
The lyrics are based on coming of age situations and teenage love. This indicates that the target audience is going to be mostly teenage girls as they can relate where as teenage boys wont be so interested in hearing a boy singing about love. The way Justin Bieber is promoted attracts a fan base of girls. During 2009, Bieber went on a tour to promote his debut single, visiting several radio stations and performing exclusively. This included American Top 40 and Radio Disney.
The 'My World Tour' was announced on March 13 2010. It started in June and is scheduled to end on December 23rd 2010 in Justin Bieber´s hometown Atlanta. Justin Timberlake was apparently in the running to sign him but he eventually signed with Usher. Usher introduced JB to the industry in April 2009 in LA just after he had finished recording his single "One Time". Usher described Bieber to the crowd as a "young phenomenon". Having Usher as he manager and mentor means he probably gains half of Ushers fan base as well. I think this was a wise move being signed with Usher as he is very successful and has a very large fan base. The songs are mostly inspired by teen romance and typical coming of age situations and the album is R&B influenced pop. The R&B being down to Ushers influence. After the albums release JB became the first solo artist in Billboard history to have at least four singles enter the Top 40of the Hot 100 before his debut album's release. This shows he has aimed at the right target audience and has promoted his album in the right way for his image.
His twitter and face book account update fans on his latest news, new releases and tour dates available.
Resources
http://en.wikipedia.org/wiki/The_Fame
http://www.thebiographychannel.co.uk/biographies/green-day.html
http://en.wikipedia.org/wiki/21st_Century_Breakdown
http://en.wikipedia.org/wiki/My_World_(EP)
