Organisations who want to take over the 2012 Olympics broadcast and press centre after the games have finished are being sought by legacy bosses.
It is hoped the two buildings, which will be used by more than 20,000 people during the games, can bring jobs and investment to east London.
Sectors such as retail, education and culture have indicated early interest, the Olympic Park Legacy Company said.
But critics said flawed design decisions will put off bidders.
Potential parties have nine weeks to put forward expressions of interest.
Andrew Altman, chief executive of the Olympic Park Legacy Company, said: "Innovation and enterprise will help define the long-term future of the Olympic Park, and the broadcast and press centres are fundamental to this through the creation of opportunities for businesses and the communities living nearby.
Jules Pipe, elected Mayor of Hackney, said: "Our vision is to see creative, digital and media industries making the centres their home and taking advantage of the creative community already thriving in the area."
But London Assembly Conservative Olympics spokesman Andrew Boff said the media centres would be "a huge shed" after the games.
All the kit which will be in place for the media will be removed after the games, Mr Boff added.
Mr Boff, who was part of an all-party committee which examined Olympic venue legacy, said there had been a lot of "chopping and changing" over the design.
Among the issues are the lack of central heating and the roof being unable to support lighting for film and TV production companies.
Mr Boff said he hoped jobs would be created but warned that the costs of moving in would put off tenants.