As a creative artist, protecting your intellectual and creative property is essential. Fortunately there are laws governing your rights to your ideas and creations. Typically you would assume that once you have an idea or create a piece of art, you would need to go and purchase a patent or copyright protection for it. However in Australia, copyright law protects individuals creative property as soon as it is materialised in a tangible form or even if the concept is simply presented verbally or recorded by any other medium.
With regards to the work I have done this trimester, namely he remix and soundalike projects, certain steps would need to be taken to avoid breaching a creators artistic rights. The remix is fairly simple, as permission was given by the artist for it to be created. For these types of situations, there is usually an agreement between the creators of the respective works. However if I was to remix a popular song such as Everlong by the Foo Fighters, I would need to gain the rights to the musical composition and the performance/recording which could most likely be obtained through the record company (i.e. Capitol Records) for a fee and possibly even a percentage of the earnings from the remix.
Speaking of earnings, it is generally okay to to use, modify and recreate copyrighted for personal uses, as long as you are not claiming it is entirely your own work. It is when it is shown publicly that the original owners of the copyright must be involved to ensure they are receiving appropriate royalties. This can be done in Australia through the non profit organisation APRA-AMCOS, which manage and distribute royalties to registered members.
As the soundalike project was recorded at an educational facility and for the purposes of education, the recording would almost definitely be covered under fair dealing. Fair dealing (sometimes confused with the American equivalent fair use) allows copyrighted material to be used for study, parody/satire, criticism and review without needing the permission of the copyright holder. If a similar project were done by a cover band that wanted to record a cover version of Everlong and release it on a record, they would need to register the cover with APRA-AMCOS and purchase a license. This will cost a fee calculated by the "selling price ÷ number of works on recording x 6.6% (the royalty rate) x amount of APRA AMCOS registered works x quantity manufactured" (APRA-AMCOS, 2017) which will be eventually payed to the original copyright holders.
In the case of doing a soundalike where you actually try to recreate the recordings, you would also need obtain permission from the record company who owns the rights to the recording, in this case, Capitol Records. You can often purchase licenses directly from record companies online for this purpose and to allow the use of their music in films and advertising.