"Explanatory Notes are documents that explain the purpose of a Bill. All Government Bills and some Private Members' Bills have an accompanying Explanatory Note. They can be found among the 'Bill documents' on the relevant Bill page" https://www.parliament.uk/site-information/glossary/explanatory-notes/ (accessed 20 November 2020)
If the case you need only has a neutral citation then you will have to use one of the online sources to find it!
Specialist court & tribunal for hearing judicial review applications
The Administrative Court and the Upper Tribunal (Immigration and Asylum Chamber or UTIAC) which has Judicial Review powers in relation to most immigration decisions.
Printed law reports
UK (& English & Welsh) law report series are shelved on Floor 2, in section with shelf marks beginning Cw UK 100 to Cw UK 200.