As you want contact details of IIM Gurukul Institute located in Nagpur, so here I am providing its contact details:

IIM Gurukul
Hanuman Nagar, Nagpur - 440009,
Opp Rashtriya Vidyalya
Ph: +(91)-712-6450947 +(91)-9021120224

I am also providing contact details of other Coaching Institutes for CAT Exam in Nagpur for your reference:

Career Launcher  
Address: 83 Hill Top, Ramnagar,
Near Ramnagar Water Tank, Dharampeth,
Nagpur, Maharashtra 440010
Phone: 0712 606 3000

Bulls Eye, Nagpur  
Address: 2nd Floor, Thakur Apartment,
Above Dosal Plaza, Amravati Road, Ravi Nagar Square,
Nagpur, Maharashtra 440010
Phone: 0712 605 0400

T.I.M.E.  
Address: Great Nag Rd, Side Of Dainik Bhaskar News Paper,
Near A.K.Gandhi Cars, Baidyanath Square,
Untkhana, Nagpur, Maharashtra 440008
Phone: 0712 645 6709

IMS Nagpur, Maharashtra  
Address: F1 & F2, Plot no. Plot no. 186, Indu Yash II,
Cement Road Above Subway Near, Baji Prabhu Deshpande Chowk,
Dharampeth Extension, Ram Nagar, Nagpur, Maharashtra 440010
Phone: 0712 255 7084

T.I.M.E.  
Address: Triumphant Institute of Management Institute Pvt. Ltd.,
1st Floor, Above Ankur Furnitures, Nirmal Bank,
Main Road, Nandanvan, Nagpur, Maharashtra 440009
Phone: 0712 329 7187

Career Forum  
Address: 225e, Opposite Times Of India,
Off Lane No 1, Canal Road, Gokulpeth,
Nagpur, Maharashtra 440010
Phone: 093717 13070